AP
Evolutionary instincts lead people to put on weight when bad news is on the horizon, a study has found.

A study found that a perception of tough times ahead, makes people more likely to seek higher calorie foods.

It kicks in a survival 'carpe diem' — seize the day — instinct, where higher calorie foods are valued at a premium, reports journal Psychological Science.

Those subconsciously primed with messages such as 'live for today' ate nearly 40 per cent more food than those subjected to neutral messages, the study from the University of Miami found.

Professor Juliano Laran said: "The findings of this study come at a time when our country is slowly recovering from the onslaught of negative presidential campaign ads chalked with topics such as the weak economy, gun violence, war, deep political divides, just to name a few problem areas.

"Now that we know this sort of messaging causes people to seek out more calories out of a survival instinct, it would be wise for those looking to kick off a healthier new year to tune out news for a while."

The study also found that when the group primed with "tough times" messages was then told the food they were sampling was low-calorie, they consumed roughly 25 percent less of the food.

According to the researchers this is because if people perceive that food resources are scarce, they place a higher value on food with more calories.

The groups were given identical foods. However, being told one was higher in calories increased its perceived worth, the study found.

Prof Laran said: "It is clear from the studies that taste was not what caused the reactions, it was a longing for calories.